Thomas maea fell



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T. M. FELL.

FURNACE.

"Patented Oct. 25,1881.

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FURNACE.

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No. 248,581. Patented Oct. 25,1881.

@GGQ @GGGGQ @OGQGQO @OQOGGGG @GGGGGDGG @GOGOGGOZ @GQQQGGG @GGOOGGGG @GOQQOGGO @GQGQOGO @GGGQGG GOGGGO @OGG J4 Ww/v UNrre STATES THOMAS MARA FELL, OF BROOKLYN, ASSIGNOR TO THE FELL BOILER IMPROVEMENT COMPANY, OF NEW YORK, N. Y.

FURNACE.

SPECIFICATION forming part of Letters Patent No. 248,581, dated October 25, 1881.

Application filed June 15, 1881. (No model.)

To all whom it may concern Be it known that I, THOMAS MARA FELL, a citizen of the United States, residing in the city of Brooklyn, in the countyof Kings, State of New York, have invented new and useful Improvements in Furnaces, of which the following is a specification.

Myinvention relates to an improved manner of fitting the fire-boxes of boilers or other furnaces with diaphragms and air-supplying devices for the better combustion of fuel.

The object of my improvements or attach ments is to secure a superior and economical combustion of fuel, which I effect by the introduction of highly-heated currents of air, and in such manner as to thoroughly mix the same with the gases of fire-combustion, and then further reheat the mixed gases and bring the whole under conditions so as to completely oxygenize such gases.

A further object of my invention is to equalize the distribution of heat and to relieve the great wear and strain upon the fire-surfaces of such furnaces.

A further object of my invention is the conversion of smoke and the carbonic-oxide gas into a higher condition of combustion and the retaining of fine coal within such furnace.

To this end my invention consists in the novel construction and arrangement of my hanging diaphragm or partition, and in the manner of suspending the same.

It also consists in the combination and arrangement of the air heating and supplying devices, in which the air, after being heated, is thrown in streams or jets toward the firedoor, and which is met with streams or jets of air entering through the perforated door, the latter being prevented from striking the crownsheet by means of adeflectorarranged over the door, the streams of air running in opposite directions, coming in contact with each other, thus forming eddies, taking up with them the gases evolved from the fuel, becoming thoroughly mixed and heated before reaching the point of combustion.

It further consists in the construction and arrangement of the bridge-wall by which the outer air is heated, a portion of the hot gases of combustion is drawn into a chamber by a jet of steam, and the whole intimately mixed, the steam and air being intensely heated by the flame or gases, which is drawn from the hottest portion of the furnace-via, the throat-and the entire mass thrown into the furnace in jets as the flame and gases pass from under the partition, and thus again causing them to come in violent contactwith each other, and thus again mixing them and causing them to impinge hard against the rear or bulge of the pendent partition, compelling them to remain longer in the furnace in contact with the flame, thus giving them the necessary time to be wholly consumed.

I attain these objects by means of the improvements forming my furnace attachments, and the mode of operation as is herein illustrated and explained by the drawings, which form a part of this specification.

Figure 1 is a vertical longitudinal section, Fig. 2 is a vertical cross-section, and Fig. 3 a half-sectional plan, of attachments or improvements as applied to the tire-box of a locomotive or similar boiler; Figs. 4 and 5, vertical longitudinal and cross sections of the attachments or improvements as applied to a cylinder or return-flue or similar boiler, and Fig. 6 a plan of side bearings.

All the letters refer to similar and corresponding parts in all the figures.

The furnace is divided into two chambers a front chamber, A, and a rear or combustion chamber, B.

0 represents the usual grate-bars, which I prefer dipping down toward the back; D, a perforated fire-door, having a regulator for the admission of air to the fuel.

The parts E,E, and E are vertical slabs of fire-proof material, constructed so that one of such slabs shall form a key-wedge for the support of the others and form a pendentpartition. I therefore prefer to use three slabs sufficiently large to extend across from one side sheet to the other, or from wall to wall.

F represents metal pins screwed into the boiler-sheets, and which fit into hollows made in the slabs; G,a horizontal air-heating space or chamber, having a number of small outlets,

H, leading into the front chamber, A, and which chamber is surrounded by an enlargementor boss, as plainly seen in Figs. 1 and 4; I, a center supporting-bar, passing down through a perforation in the center of the key-slab E, and screwed into a short perforated pipe, K, within the heating-chamber. This arrangement, while it permits the free passage of air, also furnishes a good support for the whole atachment.

The two side slabs, E and E of Figs. 4 and 5 are made to fit the form of the sides or walls, and extend up to thelugs L, or, in locomotiveboilers, to the crown-sheet, as shown in Figs. 1 and 2.

Around the outside edges of all the slabs, except the lower edges over the fire, is constructed a groove, M, which allows the slabs to be fitted either over aline of rivet-heads, as shown at M of Fig. 3, or over corrugations on the side sheets, the purpose of which is to prevent an escape of gas in that direction, and to secure a firm side support.

N are short tubes or thimbles swelled into the water-ways, Fig. 2; O, air-tubes filling the same, and projecting a few inches into the chamber G, fitted on the outside by a collar or nut, and their purpose is to supply an additional support to the side slabs and permit the entrance of air. A modification of this arrangement is necessitated in the case of furnaces having brick walls for sides instead of water ways or legs, as in Fig. 5, wherein the side pins, F, instead of being screwed into the sheets, are inserted through the thickness of the wall, and instead of the shortwrought-iron or copper tubes or thimbles N being swelled into the legs or water-ways,I use a heavier substitute, a plan of which is given in Fig. 6.

The lower projecting portion of the slabs, as seen in Figs. 1 and 2, and marked P, is omitted in furnaces having a short space or distance between the lower part of the boiler and the surface of the fire-bars. The center or key slab has a projecting tongue on both sides Q, and which fit into corresponding grooves on the edges of the two side slabs. (See Fig. 3 and the dotted lines shown in Figs. 2 and 5.)

R is a deflecting-plate, and S, Fig. 1, a circulating-plate, the uses and objects of which are the preservation of the crown-sheet from the effects of cold air entering by way of the door, and a rapid circulation of water to offset the effect of the heat on the back sheet.

The depth from the bottom of return tubular or similar boilers to the fire-bars being much less than in locomotive-boilers necessitates the removal of a portion of the valuable heatingsurface of the slabs, or that portion marked P, Fig. 1. I therefore introduce for these kinds of boilers a second hot-blast for the purpose of utilizing any escaping combustible gas, and which I accomplish by the arrangement of bridge-walls, as is shown in Figs. 4 and 5, in which- T is a slab, partition, or wall; U, air-ducts, constructed in the thickness of the bridge wall,

permitting air to pass from the ash -pit and exit at the pointV above the fuel in jets. W is ajet of steam, which acts as an injector; X, an opening, having a flaring mouth, and Yan iron plate, with a door opening into the space between the front bridge-wall and the slab or wall T, for the purpose of removing dust, &c. This arrangement furnishes a highly -lieate(l supply of fresh oxygen, as the force of the steam-jet not only draws in the air, but alsoa sufficient quantity of the highly'heated gases from those passing over the bridge-wall.

A modification of the bar or bolt I, which becomes necessary when a line of tubes interfere with the insertion of the nut, as before specified, is seen in Fig.5. Instead of the nut, the bar or bolt is screwed direct into the boiler-sheet, and in order to suspend the key-slab two holes are made through thepipe K, which is then held up by the collar on the bar or bolt, as is shown.

To secure as perfect combustion of the fuelgases as is possible, it is not enough that. cold air be admitted under a body of coal. It requires that such gases be reheated and oxygenated after leaving the fuel, and at a much higher temperature than can be usually obtained in the upper part of a furnace or over the fuel. Air passing into a body of fuel is almost immediately deoxidized, and hence the bulk of the heat is produced in the first two or three inches of contact or near the gratebars. Thisheat,passingupthroughtheremaining thickness of the fuel, is sufficient, however, to distill ofi" a much greater quantity of carbon than can be brought into the higher combustion. My mode of operation permits an economical use of a deep fire, and it is therefore of especial use in the boxes of locomotiveboilers.

The operation is as follows: Air is freely admitted without check to the under side of the fire'bars by way of the ashpit, the result being the usual development of large quantities of highlycarbonized gases, which, instead of passing direct through the fines or out of the furnace,aredetained andintimatelymixedwith a current ofhighly-heatcd air, which enters the chamber A by the small air-ducts H, by way of the heating chamber G and air pipes 0. This air is made toenter horizontally in fine streams and directly against the other stream of air, which enters by way of the perforated door D, and which becomes heated on its passage to the fire. The gases arising from the fuel are thus well-mixed before passing around into the back or combustion chamber, B; but in so passing become heated sufficiently to bring about the desired combustion.

I prefer to use the grate-bars lowered at the back end, in order that the lesser depth of fuel in the front chamber may offer the least resistance for the entrance of air in that direction; but should it be impracticable to so lower them, a dead-plate, which may also form a damper, may be used in the back chamber, as shown in Fig. 1. Fine cinder or coal thrown up by the action of a blast is precipitated back into the hottest part of the tire, and is there consumed and the dust retained at the bottom of the chamber B.

5 i find that it is more advantageous to pass the gases of combustion just over a body of fuel than through it, as gases when passed through the fuel tend to reunite with their former elements, and thus destroy the effect of perfect to combustion. I therefore leave a clear open space sufficiently large between the bottom edge of the slabs and the top of the surface of the fuel, as shown by the dotted lines, for the free escape of the gases, but yet close enough to act as a check upon a too free exit.

One great advantage of my arrangement of slabs is that although securely fixed, yet there is no iron exposed to the action of the fire.

As a modification of the manner of fitting in the pipes O and K, especially for narrow furnaces, such pipes may be joined together, and so constitute one long perforated tube.

VVhatl claim as my invention is-- 1. In a furnace, a pendent division plate or partition extending from the crown-sheet to near the surface of the fuel, said partition being provided with air-apertures toward the front, and air-pipe G, in combination with a perforated door, substantially as described.

2. The combination,in afurnace, ofapendent partition or attachments extending from the crown-sheet to near the surface of the fuel, with a perforated door and inclined grate-bars, in the manner shown and described.

3. The combination,in afurnace, of the ban ging partition, made upof sections and adapted to supply air to the furnace through it, and a perforated door andrearwardly-inclined gratebars, with the rear water-leg, said water-leg be- 0 ing provided with a'circulating-plate, whereby the extreme heat at the mouth of the flue will be prevented from burning or blistering said sheet, in the manner shown.

4. The combination, in a smoke-burnin g furnace, of the perforated door and the shield R with han gin g partitioitperforated in the front, as described, for the introduction of hot air, whereby the cold air entering the door is prevented from striking the crown-sheet and deflecting it down to and causing it to mix with the hot gases, as described.

5. The combination, in a furnace, of a hanging partition arranged across the furnace, dividing said furnace into front and rear chambers, A and B, said partition being composed of sections E E E and adapted to be retained in place by pins F, and air-pipe G, in the manner shown and described.

6. The combination, in a furnace, of a hanging partition located across the furnace, consisting of two or more side sections wider at their tops than at their bottoms, and a central key-section wider at its bottom than at its top, the side sections having A-shaped recesses and the central section being provided with a corresponding projection, so that when the key or central section is entered it will slide wedgelike to its place, thus binding and securing the side sections in position, in the manner shown and described.

7. The combination, in a boiler or other furnace for the more perfect combustion of fuel, of the hollow pendent partition and the hollow bridge-wall, constructed with an air-inlet, U, combustible gas-flue X, and steam-jet W, the bridge-wall having perforations toward the hanging partition, in the manner and for the purpose set forth.

THOMAS M. FELL.

Witnesses: 1

H. HOLSOHULO, J.,G. BURRILL. 

